linux/drivers/idle/intel_idle.c
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   1/*
   2 * intel_idle.c - native hardware idle loop for modern Intel processors
   3 *
   4 * Copyright (c) 2013, Intel Corporation.
   5 * Len Brown <len.brown@intel.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify it
   8 * under the terms and conditions of the GNU General Public License,
   9 * version 2, as published by the Free Software Foundation.
  10 *
  11 * This program is distributed in the hope it will be useful, but WITHOUT
  12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14 * more details.
  15 *
  16 * You should have received a copy of the GNU General Public License along with
  17 * this program; if not, write to the Free Software Foundation, Inc.,
  18 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21/*
  22 * intel_idle is a cpuidle driver that loads on specific Intel processors
  23 * in lieu of the legacy ACPI processor_idle driver.  The intent is to
  24 * make Linux more efficient on these processors, as intel_idle knows
  25 * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs.
  26 */
  27
  28/*
  29 * Design Assumptions
  30 *
  31 * All CPUs have same idle states as boot CPU
  32 *
  33 * Chipset BM_STS (bus master status) bit is a NOP
  34 *      for preventing entry into deep C-stats
  35 */
  36
  37/*
  38 * Known limitations
  39 *
  40 * The driver currently initializes for_each_online_cpu() upon modprobe.
  41 * It it unaware of subsequent processors hot-added to the system.
  42 * This means that if you boot with maxcpus=n and later online
  43 * processors above n, those processors will use C1 only.
  44 *
  45 * ACPI has a .suspend hack to turn off deep c-statees during suspend
  46 * to avoid complications with the lapic timer workaround.
  47 * Have not seen issues with suspend, but may need same workaround here.
  48 *
  49 * There is currently no kernel-based automatic probing/loading mechanism
  50 * if the driver is built as a module.
  51 */
  52
  53/* un-comment DEBUG to enable pr_debug() statements */
  54#define DEBUG
  55
  56#include <linux/kernel.h>
  57#include <linux/cpuidle.h>
  58#include <linux/tick.h>
  59#include <trace/events/power.h>
  60#include <linux/sched.h>
  61#include <linux/notifier.h>
  62#include <linux/cpu.h>
  63#include <linux/module.h>
  64#include <asm/cpu_device_id.h>
  65#include <asm/mwait.h>
  66#include <asm/msr.h>
  67
  68#define INTEL_IDLE_VERSION "0.4.1"
  69#define PREFIX "intel_idle: "
  70
  71static struct cpuidle_driver intel_idle_driver = {
  72        .name = "intel_idle",
  73        .owner = THIS_MODULE,
  74};
  75/* intel_idle.max_cstate=0 disables driver */
  76static int max_cstate = CPUIDLE_STATE_MAX - 1;
  77
  78static unsigned int mwait_substates;
  79
  80#define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF
  81/* Reliable LAPIC Timer States, bit 1 for C1 etc.  */
  82static unsigned int lapic_timer_reliable_states = (1 << 1);      /* Default to only C1 */
  83
  84struct idle_cpu {
  85        struct cpuidle_state *state_table;
  86
  87        /*
  88         * Hardware C-state auto-demotion may not always be optimal.
  89         * Indicate which enable bits to clear here.
  90         */
  91        unsigned long auto_demotion_disable_flags;
  92        bool byt_auto_demotion_disable_flag;
  93        bool disable_promotion_to_c1e;
  94};
  95
  96static const struct idle_cpu *icpu;
  97static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
  98static int intel_idle(struct cpuidle_device *dev,
  99                        struct cpuidle_driver *drv, int index);
 100static void intel_idle_freeze(struct cpuidle_device *dev,
 101                              struct cpuidle_driver *drv, int index);
 102static int intel_idle_cpu_init(int cpu);
 103
 104static struct cpuidle_state *cpuidle_state_table;
 105
 106/*
 107 * Set this flag for states where the HW flushes the TLB for us
 108 * and so we don't need cross-calls to keep it consistent.
 109 * If this flag is set, SW flushes the TLB, so even if the
 110 * HW doesn't do the flushing, this flag is safe to use.
 111 */
 112#define CPUIDLE_FLAG_TLB_FLUSHED        0x10000
 113
 114/*
 115 * MWAIT takes an 8-bit "hint" in EAX "suggesting"
 116 * the C-state (top nibble) and sub-state (bottom nibble)
 117 * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
 118 *
 119 * We store the hint at the top of our "flags" for each state.
 120 */
 121#define flg2MWAIT(flags) (((flags) >> 24) & 0xFF)
 122#define MWAIT2flg(eax) ((eax & 0xFF) << 24)
 123
 124/*
 125 * States are indexed by the cstate number,
 126 * which is also the index into the MWAIT hint array.
 127 * Thus C0 is a dummy.
 128 */
 129static struct cpuidle_state nehalem_cstates[] = {
 130        {
 131                .name = "C1-NHM",
 132                .desc = "MWAIT 0x00",
 133                .flags = MWAIT2flg(0x00),
 134                .exit_latency = 3,
 135                .target_residency = 6,
 136                .enter = &intel_idle,
 137                .enter_freeze = intel_idle_freeze, },
 138        {
 139                .name = "C1E-NHM",
 140                .desc = "MWAIT 0x01",
 141                .flags = MWAIT2flg(0x01),
 142                .exit_latency = 10,
 143                .target_residency = 20,
 144                .enter = &intel_idle,
 145                .enter_freeze = intel_idle_freeze, },
 146        {
 147                .name = "C3-NHM",
 148                .desc = "MWAIT 0x10",
 149                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 150                .exit_latency = 20,
 151                .target_residency = 80,
 152                .enter = &intel_idle,
 153                .enter_freeze = intel_idle_freeze, },
 154        {
 155                .name = "C6-NHM",
 156                .desc = "MWAIT 0x20",
 157                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 158                .exit_latency = 200,
 159                .target_residency = 800,
 160                .enter = &intel_idle,
 161                .enter_freeze = intel_idle_freeze, },
 162        {
 163                .enter = NULL }
 164};
 165
 166static struct cpuidle_state snb_cstates[] = {
 167        {
 168                .name = "C1-SNB",
 169                .desc = "MWAIT 0x00",
 170                .flags = MWAIT2flg(0x00),
 171                .exit_latency = 2,
 172                .target_residency = 2,
 173                .enter = &intel_idle,
 174                .enter_freeze = intel_idle_freeze, },
 175        {
 176                .name = "C1E-SNB",
 177                .desc = "MWAIT 0x01",
 178                .flags = MWAIT2flg(0x01),
 179                .exit_latency = 10,
 180                .target_residency = 20,
 181                .enter = &intel_idle,
 182                .enter_freeze = intel_idle_freeze, },
 183        {
 184                .name = "C3-SNB",
 185                .desc = "MWAIT 0x10",
 186                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 187                .exit_latency = 80,
 188                .target_residency = 211,
 189                .enter = &intel_idle,
 190                .enter_freeze = intel_idle_freeze, },
 191        {
 192                .name = "C6-SNB",
 193                .desc = "MWAIT 0x20",
 194                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 195                .exit_latency = 104,
 196                .target_residency = 345,
 197                .enter = &intel_idle,
 198                .enter_freeze = intel_idle_freeze, },
 199        {
 200                .name = "C7-SNB",
 201                .desc = "MWAIT 0x30",
 202                .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 203                .exit_latency = 109,
 204                .target_residency = 345,
 205                .enter = &intel_idle,
 206                .enter_freeze = intel_idle_freeze, },
 207        {
 208                .enter = NULL }
 209};
 210
 211static struct cpuidle_state byt_cstates[] = {
 212        {
 213                .name = "C1-BYT",
 214                .desc = "MWAIT 0x00",
 215                .flags = MWAIT2flg(0x00),
 216                .exit_latency = 1,
 217                .target_residency = 1,
 218                .enter = &intel_idle,
 219                .enter_freeze = intel_idle_freeze, },
 220        {
 221                .name = "C6N-BYT",
 222                .desc = "MWAIT 0x58",
 223                .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
 224                .exit_latency = 300,
 225                .target_residency = 275,
 226                .enter = &intel_idle,
 227                .enter_freeze = intel_idle_freeze, },
 228        {
 229                .name = "C6S-BYT",
 230                .desc = "MWAIT 0x52",
 231                .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 232                .exit_latency = 500,
 233                .target_residency = 560,
 234                .enter = &intel_idle,
 235                .enter_freeze = intel_idle_freeze, },
 236        {
 237                .name = "C7-BYT",
 238                .desc = "MWAIT 0x60",
 239                .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 240                .exit_latency = 1200,
 241                .target_residency = 4000,
 242                .enter = &intel_idle,
 243                .enter_freeze = intel_idle_freeze, },
 244        {
 245                .name = "C7S-BYT",
 246                .desc = "MWAIT 0x64",
 247                .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
 248                .exit_latency = 10000,
 249                .target_residency = 20000,
 250                .enter = &intel_idle,
 251                .enter_freeze = intel_idle_freeze, },
 252        {
 253                .enter = NULL }
 254};
 255
 256static struct cpuidle_state cht_cstates[] = {
 257        {
 258                .name = "C1-CHT",
 259                .desc = "MWAIT 0x00",
 260                .flags = MWAIT2flg(0x00),
 261                .exit_latency = 1,
 262                .target_residency = 1,
 263                .enter = &intel_idle,
 264                .enter_freeze = intel_idle_freeze, },
 265        {
 266                .name = "C6N-CHT",
 267                .desc = "MWAIT 0x58",
 268                .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
 269                .exit_latency = 80,
 270                .target_residency = 275,
 271                .enter = &intel_idle,
 272                .enter_freeze = intel_idle_freeze, },
 273        {
 274                .name = "C6S-CHT",
 275                .desc = "MWAIT 0x52",
 276                .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 277                .exit_latency = 200,
 278                .target_residency = 560,
 279                .enter = &intel_idle,
 280                .enter_freeze = intel_idle_freeze, },
 281        {
 282                .name = "C7-CHT",
 283                .desc = "MWAIT 0x60",
 284                .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 285                .exit_latency = 1200,
 286                .target_residency = 4000,
 287                .enter = &intel_idle,
 288                .enter_freeze = intel_idle_freeze, },
 289        {
 290                .name = "C7S-CHT",
 291                .desc = "MWAIT 0x64",
 292                .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
 293                .exit_latency = 10000,
 294                .target_residency = 20000,
 295                .enter = &intel_idle,
 296                .enter_freeze = intel_idle_freeze, },
 297        {
 298                .enter = NULL }
 299};
 300
 301static struct cpuidle_state ivb_cstates[] = {
 302        {
 303                .name = "C1-IVB",
 304                .desc = "MWAIT 0x00",
 305                .flags = MWAIT2flg(0x00),
 306                .exit_latency = 1,
 307                .target_residency = 1,
 308                .enter = &intel_idle,
 309                .enter_freeze = intel_idle_freeze, },
 310        {
 311                .name = "C1E-IVB",
 312                .desc = "MWAIT 0x01",
 313                .flags = MWAIT2flg(0x01),
 314                .exit_latency = 10,
 315                .target_residency = 20,
 316                .enter = &intel_idle,
 317                .enter_freeze = intel_idle_freeze, },
 318        {
 319                .name = "C3-IVB",
 320                .desc = "MWAIT 0x10",
 321                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 322                .exit_latency = 59,
 323                .target_residency = 156,
 324                .enter = &intel_idle,
 325                .enter_freeze = intel_idle_freeze, },
 326        {
 327                .name = "C6-IVB",
 328                .desc = "MWAIT 0x20",
 329                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 330                .exit_latency = 80,
 331                .target_residency = 300,
 332                .enter = &intel_idle,
 333                .enter_freeze = intel_idle_freeze, },
 334        {
 335                .name = "C7-IVB",
 336                .desc = "MWAIT 0x30",
 337                .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 338                .exit_latency = 87,
 339                .target_residency = 300,
 340                .enter = &intel_idle,
 341                .enter_freeze = intel_idle_freeze, },
 342        {
 343                .enter = NULL }
 344};
 345
 346static struct cpuidle_state ivt_cstates[] = {
 347        {
 348                .name = "C1-IVT",
 349                .desc = "MWAIT 0x00",
 350                .flags = MWAIT2flg(0x00),
 351                .exit_latency = 1,
 352                .target_residency = 1,
 353                .enter = &intel_idle,
 354                .enter_freeze = intel_idle_freeze, },
 355        {
 356                .name = "C1E-IVT",
 357                .desc = "MWAIT 0x01",
 358                .flags = MWAIT2flg(0x01),
 359                .exit_latency = 10,
 360                .target_residency = 80,
 361                .enter = &intel_idle,
 362                .enter_freeze = intel_idle_freeze, },
 363        {
 364                .name = "C3-IVT",
 365                .desc = "MWAIT 0x10",
 366                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 367                .exit_latency = 59,
 368                .target_residency = 156,
 369                .enter = &intel_idle,
 370                .enter_freeze = intel_idle_freeze, },
 371        {
 372                .name = "C6-IVT",
 373                .desc = "MWAIT 0x20",
 374                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 375                .exit_latency = 82,
 376                .target_residency = 300,
 377                .enter = &intel_idle,
 378                .enter_freeze = intel_idle_freeze, },
 379        {
 380                .enter = NULL }
 381};
 382
 383static struct cpuidle_state ivt_cstates_4s[] = {
 384        {
 385                .name = "C1-IVT-4S",
 386                .desc = "MWAIT 0x00",
 387                .flags = MWAIT2flg(0x00),
 388                .exit_latency = 1,
 389                .target_residency = 1,
 390                .enter = &intel_idle,
 391                .enter_freeze = intel_idle_freeze, },
 392        {
 393                .name = "C1E-IVT-4S",
 394                .desc = "MWAIT 0x01",
 395                .flags = MWAIT2flg(0x01),
 396                .exit_latency = 10,
 397                .target_residency = 250,
 398                .enter = &intel_idle,
 399                .enter_freeze = intel_idle_freeze, },
 400        {
 401                .name = "C3-IVT-4S",
 402                .desc = "MWAIT 0x10",
 403                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 404                .exit_latency = 59,
 405                .target_residency = 300,
 406                .enter = &intel_idle,
 407                .enter_freeze = intel_idle_freeze, },
 408        {
 409                .name = "C6-IVT-4S",
 410                .desc = "MWAIT 0x20",
 411                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 412                .exit_latency = 84,
 413                .target_residency = 400,
 414                .enter = &intel_idle,
 415                .enter_freeze = intel_idle_freeze, },
 416        {
 417                .enter = NULL }
 418};
 419
 420static struct cpuidle_state ivt_cstates_8s[] = {
 421        {
 422                .name = "C1-IVT-8S",
 423                .desc = "MWAIT 0x00",
 424                .flags = MWAIT2flg(0x00),
 425                .exit_latency = 1,
 426                .target_residency = 1,
 427                .enter = &intel_idle,
 428                .enter_freeze = intel_idle_freeze, },
 429        {
 430                .name = "C1E-IVT-8S",
 431                .desc = "MWAIT 0x01",
 432                .flags = MWAIT2flg(0x01),
 433                .exit_latency = 10,
 434                .target_residency = 500,
 435                .enter = &intel_idle,
 436                .enter_freeze = intel_idle_freeze, },
 437        {
 438                .name = "C3-IVT-8S",
 439                .desc = "MWAIT 0x10",
 440                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 441                .exit_latency = 59,
 442                .target_residency = 600,
 443                .enter = &intel_idle,
 444                .enter_freeze = intel_idle_freeze, },
 445        {
 446                .name = "C6-IVT-8S",
 447                .desc = "MWAIT 0x20",
 448                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 449                .exit_latency = 88,
 450                .target_residency = 700,
 451                .enter = &intel_idle,
 452                .enter_freeze = intel_idle_freeze, },
 453        {
 454                .enter = NULL }
 455};
 456
 457static struct cpuidle_state hsw_cstates[] = {
 458        {
 459                .name = "C1-HSW",
 460                .desc = "MWAIT 0x00",
 461                .flags = MWAIT2flg(0x00),
 462                .exit_latency = 2,
 463                .target_residency = 2,
 464                .enter = &intel_idle,
 465                .enter_freeze = intel_idle_freeze, },
 466        {
 467                .name = "C1E-HSW",
 468                .desc = "MWAIT 0x01",
 469                .flags = MWAIT2flg(0x01),
 470                .exit_latency = 10,
 471                .target_residency = 20,
 472                .enter = &intel_idle,
 473                .enter_freeze = intel_idle_freeze, },
 474        {
 475                .name = "C3-HSW",
 476                .desc = "MWAIT 0x10",
 477                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 478                .exit_latency = 33,
 479                .target_residency = 100,
 480                .enter = &intel_idle,
 481                .enter_freeze = intel_idle_freeze, },
 482        {
 483                .name = "C6-HSW",
 484                .desc = "MWAIT 0x20",
 485                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 486                .exit_latency = 133,
 487                .target_residency = 400,
 488                .enter = &intel_idle,
 489                .enter_freeze = intel_idle_freeze, },
 490        {
 491                .name = "C7s-HSW",
 492                .desc = "MWAIT 0x32",
 493                .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
 494                .exit_latency = 166,
 495                .target_residency = 500,
 496                .enter = &intel_idle,
 497                .enter_freeze = intel_idle_freeze, },
 498        {
 499                .name = "C8-HSW",
 500                .desc = "MWAIT 0x40",
 501                .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 502                .exit_latency = 300,
 503                .target_residency = 900,
 504                .enter = &intel_idle,
 505                .enter_freeze = intel_idle_freeze, },
 506        {
 507                .name = "C9-HSW",
 508                .desc = "MWAIT 0x50",
 509                .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 510                .exit_latency = 600,
 511                .target_residency = 1800,
 512                .enter = &intel_idle,
 513                .enter_freeze = intel_idle_freeze, },
 514        {
 515                .name = "C10-HSW",
 516                .desc = "MWAIT 0x60",
 517                .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 518                .exit_latency = 2600,
 519                .target_residency = 7700,
 520                .enter = &intel_idle,
 521                .enter_freeze = intel_idle_freeze, },
 522        {
 523                .enter = NULL }
 524};
 525static struct cpuidle_state bdw_cstates[] = {
 526        {
 527                .name = "C1-BDW",
 528                .desc = "MWAIT 0x00",
 529                .flags = MWAIT2flg(0x00),
 530                .exit_latency = 2,
 531                .target_residency = 2,
 532                .enter = &intel_idle,
 533                .enter_freeze = intel_idle_freeze, },
 534        {
 535                .name = "C1E-BDW",
 536                .desc = "MWAIT 0x01",
 537                .flags = MWAIT2flg(0x01),
 538                .exit_latency = 10,
 539                .target_residency = 20,
 540                .enter = &intel_idle,
 541                .enter_freeze = intel_idle_freeze, },
 542        {
 543                .name = "C3-BDW",
 544                .desc = "MWAIT 0x10",
 545                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 546                .exit_latency = 40,
 547                .target_residency = 100,
 548                .enter = &intel_idle,
 549                .enter_freeze = intel_idle_freeze, },
 550        {
 551                .name = "C6-BDW",
 552                .desc = "MWAIT 0x20",
 553                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 554                .exit_latency = 133,
 555                .target_residency = 400,
 556                .enter = &intel_idle,
 557                .enter_freeze = intel_idle_freeze, },
 558        {
 559                .name = "C7s-BDW",
 560                .desc = "MWAIT 0x32",
 561                .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
 562                .exit_latency = 166,
 563                .target_residency = 500,
 564                .enter = &intel_idle,
 565                .enter_freeze = intel_idle_freeze, },
 566        {
 567                .name = "C8-BDW",
 568                .desc = "MWAIT 0x40",
 569                .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 570                .exit_latency = 300,
 571                .target_residency = 900,
 572                .enter = &intel_idle,
 573                .enter_freeze = intel_idle_freeze, },
 574        {
 575                .name = "C9-BDW",
 576                .desc = "MWAIT 0x50",
 577                .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 578                .exit_latency = 600,
 579                .target_residency = 1800,
 580                .enter = &intel_idle,
 581                .enter_freeze = intel_idle_freeze, },
 582        {
 583                .name = "C10-BDW",
 584                .desc = "MWAIT 0x60",
 585                .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 586                .exit_latency = 2600,
 587                .target_residency = 7700,
 588                .enter = &intel_idle,
 589                .enter_freeze = intel_idle_freeze, },
 590        {
 591                .enter = NULL }
 592};
 593
 594static struct cpuidle_state skl_cstates[] = {
 595        {
 596                .name = "C1-SKL",
 597                .desc = "MWAIT 0x00",
 598                .flags = MWAIT2flg(0x00),
 599                .exit_latency = 2,
 600                .target_residency = 2,
 601                .enter = &intel_idle,
 602                .enter_freeze = intel_idle_freeze, },
 603        {
 604                .name = "C1E-SKL",
 605                .desc = "MWAIT 0x01",
 606                .flags = MWAIT2flg(0x01),
 607                .exit_latency = 10,
 608                .target_residency = 20,
 609                .enter = &intel_idle,
 610                .enter_freeze = intel_idle_freeze, },
 611        {
 612                .name = "C3-SKL",
 613                .desc = "MWAIT 0x10",
 614                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 615                .exit_latency = 70,
 616                .target_residency = 100,
 617                .enter = &intel_idle,
 618                .enter_freeze = intel_idle_freeze, },
 619        {
 620                .name = "C6-SKL",
 621                .desc = "MWAIT 0x20",
 622                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 623                .exit_latency = 85,
 624                .target_residency = 200,
 625                .enter = &intel_idle,
 626                .enter_freeze = intel_idle_freeze, },
 627        {
 628                .name = "C7s-SKL",
 629                .desc = "MWAIT 0x33",
 630                .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED,
 631                .exit_latency = 124,
 632                .target_residency = 800,
 633                .enter = &intel_idle,
 634                .enter_freeze = intel_idle_freeze, },
 635        {
 636                .name = "C8-SKL",
 637                .desc = "MWAIT 0x40",
 638                .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 639                .exit_latency = 200,
 640                .target_residency = 800,
 641                .enter = &intel_idle,
 642                .enter_freeze = intel_idle_freeze, },
 643        {
 644                .name = "C9-SKL",
 645                .desc = "MWAIT 0x50",
 646                .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 647                .exit_latency = 480,
 648                .target_residency = 5000,
 649                .enter = &intel_idle,
 650                .enter_freeze = intel_idle_freeze, },
 651        {
 652                .name = "C10-SKL",
 653                .desc = "MWAIT 0x60",
 654                .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 655                .exit_latency = 890,
 656                .target_residency = 5000,
 657                .enter = &intel_idle,
 658                .enter_freeze = intel_idle_freeze, },
 659        {
 660                .enter = NULL }
 661};
 662
 663static struct cpuidle_state skx_cstates[] = {
 664        {
 665                .name = "C1-SKX",
 666                .desc = "MWAIT 0x00",
 667                .flags = MWAIT2flg(0x00),
 668                .exit_latency = 2,
 669                .target_residency = 2,
 670                .enter = &intel_idle,
 671                .enter_freeze = intel_idle_freeze, },
 672        {
 673                .name = "C1E-SKX",
 674                .desc = "MWAIT 0x01",
 675                .flags = MWAIT2flg(0x01),
 676                .exit_latency = 10,
 677                .target_residency = 20,
 678                .enter = &intel_idle,
 679                .enter_freeze = intel_idle_freeze, },
 680        {
 681                .name = "C6-SKX",
 682                .desc = "MWAIT 0x20",
 683                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 684                .exit_latency = 133,
 685                .target_residency = 600,
 686                .enter = &intel_idle,
 687                .enter_freeze = intel_idle_freeze, },
 688        {
 689                .enter = NULL }
 690};
 691
 692static struct cpuidle_state atom_cstates[] = {
 693        {
 694                .name = "C1E-ATM",
 695                .desc = "MWAIT 0x00",
 696                .flags = MWAIT2flg(0x00),
 697                .exit_latency = 10,
 698                .target_residency = 20,
 699                .enter = &intel_idle,
 700                .enter_freeze = intel_idle_freeze, },
 701        {
 702                .name = "C2-ATM",
 703                .desc = "MWAIT 0x10",
 704                .flags = MWAIT2flg(0x10),
 705                .exit_latency = 20,
 706                .target_residency = 80,
 707                .enter = &intel_idle,
 708                .enter_freeze = intel_idle_freeze, },
 709        {
 710                .name = "C4-ATM",
 711                .desc = "MWAIT 0x30",
 712                .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 713                .exit_latency = 100,
 714                .target_residency = 400,
 715                .enter = &intel_idle,
 716                .enter_freeze = intel_idle_freeze, },
 717        {
 718                .name = "C6-ATM",
 719                .desc = "MWAIT 0x52",
 720                .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 721                .exit_latency = 140,
 722                .target_residency = 560,
 723                .enter = &intel_idle,
 724                .enter_freeze = intel_idle_freeze, },
 725        {
 726                .enter = NULL }
 727};
 728static struct cpuidle_state avn_cstates[] = {
 729        {
 730                .name = "C1-AVN",
 731                .desc = "MWAIT 0x00",
 732                .flags = MWAIT2flg(0x00),
 733                .exit_latency = 2,
 734                .target_residency = 2,
 735                .enter = &intel_idle,
 736                .enter_freeze = intel_idle_freeze, },
 737        {
 738                .name = "C6-AVN",
 739                .desc = "MWAIT 0x51",
 740                .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED,
 741                .exit_latency = 15,
 742                .target_residency = 45,
 743                .enter = &intel_idle,
 744                .enter_freeze = intel_idle_freeze, },
 745        {
 746                .enter = NULL }
 747};
 748static struct cpuidle_state knl_cstates[] = {
 749        {
 750                .name = "C1-KNL",
 751                .desc = "MWAIT 0x00",
 752                .flags = MWAIT2flg(0x00),
 753                .exit_latency = 1,
 754                .target_residency = 2,
 755                .enter = &intel_idle,
 756                .enter_freeze = intel_idle_freeze },
 757        {
 758                .name = "C6-KNL",
 759                .desc = "MWAIT 0x10",
 760                .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 761                .exit_latency = 120,
 762                .target_residency = 500,
 763                .enter = &intel_idle,
 764                .enter_freeze = intel_idle_freeze },
 765        {
 766                .enter = NULL }
 767};
 768
 769static struct cpuidle_state bxt_cstates[] = {
 770        {
 771                .name = "C1-BXT",
 772                .desc = "MWAIT 0x00",
 773                .flags = MWAIT2flg(0x00),
 774                .exit_latency = 2,
 775                .target_residency = 2,
 776                .enter = &intel_idle,
 777                .enter_freeze = intel_idle_freeze, },
 778        {
 779                .name = "C1E-BXT",
 780                .desc = "MWAIT 0x01",
 781                .flags = MWAIT2flg(0x01),
 782                .exit_latency = 10,
 783                .target_residency = 20,
 784                .enter = &intel_idle,
 785                .enter_freeze = intel_idle_freeze, },
 786        {
 787                .name = "C6-BXT",
 788                .desc = "MWAIT 0x20",
 789                .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 790                .exit_latency = 133,
 791                .target_residency = 133,
 792                .enter = &intel_idle,
 793                .enter_freeze = intel_idle_freeze, },
 794        {
 795                .name = "C7s-BXT",
 796                .desc = "MWAIT 0x31",
 797                .flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED,
 798                .exit_latency = 155,
 799                .target_residency = 155,
 800                .enter = &intel_idle,
 801                .enter_freeze = intel_idle_freeze, },
 802        {
 803                .name = "C8-BXT",
 804                .desc = "MWAIT 0x40",
 805                .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 806                .exit_latency = 1000,
 807                .target_residency = 1000,
 808                .enter = &intel_idle,
 809                .enter_freeze = intel_idle_freeze, },
 810        {
 811                .name = "C9-BXT",
 812                .desc = "MWAIT 0x50",
 813                .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 814                .exit_latency = 2000,
 815                .target_residency = 2000,
 816                .enter = &intel_idle,
 817                .enter_freeze = intel_idle_freeze, },
 818        {
 819                .name = "C10-BXT",
 820                .desc = "MWAIT 0x60",
 821                .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 822                .exit_latency = 10000,
 823                .target_residency = 10000,
 824                .enter = &intel_idle,
 825                .enter_freeze = intel_idle_freeze, },
 826        {
 827                .enter = NULL }
 828};
 829
 830/**
 831 * intel_idle
 832 * @dev: cpuidle_device
 833 * @drv: cpuidle driver
 834 * @index: index of cpuidle state
 835 *
 836 * Must be called under local_irq_disable().
 837 */
 838static int intel_idle(struct cpuidle_device *dev,
 839                struct cpuidle_driver *drv, int index)
 840{
 841        unsigned long ecx = 1; /* break on interrupt flag */
 842        struct cpuidle_state *state = &drv->states[index];
 843        unsigned long eax = flg2MWAIT(state->flags);
 844        unsigned int cstate;
 845        int cpu = smp_processor_id();
 846
 847        cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1;
 848
 849        /*
 850         * leave_mm() to avoid costly and often unnecessary wakeups
 851         * for flushing the user TLB's associated with the active mm.
 852         */
 853        if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED)
 854                leave_mm(cpu);
 855
 856        if (!(lapic_timer_reliable_states & (1 << (cstate))))
 857                tick_broadcast_enter();
 858
 859        mwait_idle_with_hints(eax, ecx);
 860
 861        if (!(lapic_timer_reliable_states & (1 << (cstate))))
 862                tick_broadcast_exit();
 863
 864        return index;
 865}
 866
 867/**
 868 * intel_idle_freeze - simplified "enter" callback routine for suspend-to-idle
 869 * @dev: cpuidle_device
 870 * @drv: cpuidle driver
 871 * @index: state index
 872 */
 873static void intel_idle_freeze(struct cpuidle_device *dev,
 874                             struct cpuidle_driver *drv, int index)
 875{
 876        unsigned long ecx = 1; /* break on interrupt flag */
 877        unsigned long eax = flg2MWAIT(drv->states[index].flags);
 878
 879        mwait_idle_with_hints(eax, ecx);
 880}
 881
 882static void __setup_broadcast_timer(void *arg)
 883{
 884        unsigned long on = (unsigned long)arg;
 885
 886        if (on)
 887                tick_broadcast_enable();
 888        else
 889                tick_broadcast_disable();
 890}
 891
 892static int cpu_hotplug_notify(struct notifier_block *n,
 893                              unsigned long action, void *hcpu)
 894{
 895        int hotcpu = (unsigned long)hcpu;
 896        struct cpuidle_device *dev;
 897
 898        switch (action & ~CPU_TASKS_FROZEN) {
 899        case CPU_ONLINE:
 900
 901                if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
 902                        smp_call_function_single(hotcpu, __setup_broadcast_timer,
 903                                                 (void *)true, 1);
 904
 905                /*
 906                 * Some systems can hotplug a cpu at runtime after
 907                 * the kernel has booted, we have to initialize the
 908                 * driver in this case
 909                 */
 910                dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu);
 911                if (dev->registered)
 912                        break;
 913
 914                if (intel_idle_cpu_init(hotcpu))
 915                        return NOTIFY_BAD;
 916
 917                break;
 918        }
 919        return NOTIFY_OK;
 920}
 921
 922static struct notifier_block cpu_hotplug_notifier = {
 923        .notifier_call = cpu_hotplug_notify,
 924};
 925
 926static void auto_demotion_disable(void *dummy)
 927{
 928        unsigned long long msr_bits;
 929
 930        rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
 931        msr_bits &= ~(icpu->auto_demotion_disable_flags);
 932        wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
 933}
 934static void c1e_promotion_disable(void *dummy)
 935{
 936        unsigned long long msr_bits;
 937
 938        rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
 939        msr_bits &= ~0x2;
 940        wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
 941}
 942
 943static const struct idle_cpu idle_cpu_nehalem = {
 944        .state_table = nehalem_cstates,
 945        .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
 946        .disable_promotion_to_c1e = true,
 947};
 948
 949static const struct idle_cpu idle_cpu_atom = {
 950        .state_table = atom_cstates,
 951};
 952
 953static const struct idle_cpu idle_cpu_lincroft = {
 954        .state_table = atom_cstates,
 955        .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE,
 956};
 957
 958static const struct idle_cpu idle_cpu_snb = {
 959        .state_table = snb_cstates,
 960        .disable_promotion_to_c1e = true,
 961};
 962
 963static const struct idle_cpu idle_cpu_byt = {
 964        .state_table = byt_cstates,
 965        .disable_promotion_to_c1e = true,
 966        .byt_auto_demotion_disable_flag = true,
 967};
 968
 969static const struct idle_cpu idle_cpu_cht = {
 970        .state_table = cht_cstates,
 971        .disable_promotion_to_c1e = true,
 972        .byt_auto_demotion_disable_flag = true,
 973};
 974
 975static const struct idle_cpu idle_cpu_ivb = {
 976        .state_table = ivb_cstates,
 977        .disable_promotion_to_c1e = true,
 978};
 979
 980static const struct idle_cpu idle_cpu_ivt = {
 981        .state_table = ivt_cstates,
 982        .disable_promotion_to_c1e = true,
 983};
 984
 985static const struct idle_cpu idle_cpu_hsw = {
 986        .state_table = hsw_cstates,
 987        .disable_promotion_to_c1e = true,
 988};
 989
 990static const struct idle_cpu idle_cpu_bdw = {
 991        .state_table = bdw_cstates,
 992        .disable_promotion_to_c1e = true,
 993};
 994
 995static const struct idle_cpu idle_cpu_skl = {
 996        .state_table = skl_cstates,
 997        .disable_promotion_to_c1e = true,
 998};
 999
1000static const struct idle_cpu idle_cpu_skx = {
1001        .state_table = skx_cstates,
1002        .disable_promotion_to_c1e = true,
1003};
1004
1005static const struct idle_cpu idle_cpu_avn = {
1006        .state_table = avn_cstates,
1007        .disable_promotion_to_c1e = true,
1008};
1009
1010static const struct idle_cpu idle_cpu_knl = {
1011        .state_table = knl_cstates,
1012};
1013
1014static const struct idle_cpu idle_cpu_bxt = {
1015        .state_table = bxt_cstates,
1016        .disable_promotion_to_c1e = true,
1017};
1018
1019#define ICPU(model, cpu) \
1020        { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu }
1021
1022static const struct x86_cpu_id intel_idle_ids[] __initconst = {
1023        ICPU(0x1a, idle_cpu_nehalem),
1024        ICPU(0x1e, idle_cpu_nehalem),
1025        ICPU(0x1f, idle_cpu_nehalem),
1026        ICPU(0x25, idle_cpu_nehalem),
1027        ICPU(0x2c, idle_cpu_nehalem),
1028        ICPU(0x2e, idle_cpu_nehalem),
1029        ICPU(0x1c, idle_cpu_atom),
1030        ICPU(0x26, idle_cpu_lincroft),
1031        ICPU(0x2f, idle_cpu_nehalem),
1032        ICPU(0x2a, idle_cpu_snb),
1033        ICPU(0x2d, idle_cpu_snb),
1034        ICPU(0x36, idle_cpu_atom),
1035        ICPU(0x37, idle_cpu_byt),
1036        ICPU(0x4c, idle_cpu_cht),
1037        ICPU(0x3a, idle_cpu_ivb),
1038        ICPU(0x3e, idle_cpu_ivt),
1039        ICPU(0x3c, idle_cpu_hsw),
1040        ICPU(0x3f, idle_cpu_hsw),
1041        ICPU(0x45, idle_cpu_hsw),
1042        ICPU(0x46, idle_cpu_hsw),
1043        ICPU(0x4d, idle_cpu_avn),
1044        ICPU(0x3d, idle_cpu_bdw),
1045        ICPU(0x47, idle_cpu_bdw),
1046        ICPU(0x4f, idle_cpu_bdw),
1047        ICPU(0x56, idle_cpu_bdw),
1048        ICPU(0x4e, idle_cpu_skl),
1049        ICPU(0x5e, idle_cpu_skl),
1050        ICPU(0x8e, idle_cpu_skl),
1051        ICPU(0x9e, idle_cpu_skl),
1052        ICPU(0x55, idle_cpu_skx),
1053        ICPU(0x57, idle_cpu_knl),
1054        ICPU(0x5c, idle_cpu_bxt),
1055        {}
1056};
1057MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids);
1058
1059/*
1060 * intel_idle_probe()
1061 */
1062static int __init intel_idle_probe(void)
1063{
1064        unsigned int eax, ebx, ecx;
1065        const struct x86_cpu_id *id;
1066
1067        if (max_cstate == 0) {
1068                pr_debug(PREFIX "disabled\n");
1069                return -EPERM;
1070        }
1071
1072        id = x86_match_cpu(intel_idle_ids);
1073        if (!id) {
1074                if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
1075                    boot_cpu_data.x86 == 6)
1076                        pr_debug(PREFIX "does not run on family %d model %d\n",
1077                                boot_cpu_data.x86, boot_cpu_data.x86_model);
1078                return -ENODEV;
1079        }
1080
1081        if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
1082                return -ENODEV;
1083
1084        cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
1085
1086        if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
1087            !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
1088            !mwait_substates)
1089                        return -ENODEV;
1090
1091        pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates);
1092
1093        icpu = (const struct idle_cpu *)id->driver_data;
1094        cpuidle_state_table = icpu->state_table;
1095
1096        pr_debug(PREFIX "v" INTEL_IDLE_VERSION
1097                " model 0x%X\n", boot_cpu_data.x86_model);
1098
1099        return 0;
1100}
1101
1102/*
1103 * intel_idle_cpuidle_devices_uninit()
1104 * Unregisters the cpuidle devices.
1105 */
1106static void intel_idle_cpuidle_devices_uninit(void)
1107{
1108        int i;
1109        struct cpuidle_device *dev;
1110
1111        for_each_online_cpu(i) {
1112                dev = per_cpu_ptr(intel_idle_cpuidle_devices, i);
1113                cpuidle_unregister_device(dev);
1114        }
1115}
1116
1117/*
1118 * ivt_idle_state_table_update(void)
1119 *
1120 * Tune IVT multi-socket targets
1121 * Assumption: num_sockets == (max_package_num + 1)
1122 */
1123static void ivt_idle_state_table_update(void)
1124{
1125        /* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
1126        int cpu, package_num, num_sockets = 1;
1127
1128        for_each_online_cpu(cpu) {
1129                package_num = topology_physical_package_id(cpu);
1130                if (package_num + 1 > num_sockets) {
1131                        num_sockets = package_num + 1;
1132
1133                        if (num_sockets > 4) {
1134                                cpuidle_state_table = ivt_cstates_8s;
1135                                return;
1136                        }
1137                }
1138        }
1139
1140        if (num_sockets > 2)
1141                cpuidle_state_table = ivt_cstates_4s;
1142
1143        /* else, 1 and 2 socket systems use default ivt_cstates */
1144}
1145
1146/*
1147 * Translate IRTL (Interrupt Response Time Limit) MSR to usec
1148 */
1149
1150static unsigned int irtl_ns_units[] = {
1151        1, 32, 1024, 32768, 1048576, 33554432, 0, 0 };
1152
1153static unsigned long long irtl_2_usec(unsigned long long irtl)
1154{
1155        unsigned long long ns;
1156
1157        ns = irtl_ns_units[(irtl >> 10) & 0x3];
1158
1159        return div64_u64((irtl & 0x3FF) * ns, 1000);
1160}
1161/*
1162 * bxt_idle_state_table_update(void)
1163 *
1164 * On BXT, we trust the IRTL to show the definitive maximum latency
1165 * We use the same value for target_residency.
1166 */
1167static void bxt_idle_state_table_update(void)
1168{
1169        unsigned long long msr;
1170
1171        rdmsrl(MSR_PKGC6_IRTL, msr);
1172        if (msr) {
1173                unsigned int usec = irtl_2_usec(msr);
1174
1175                bxt_cstates[2].exit_latency = usec;
1176                bxt_cstates[2].target_residency = usec;
1177        }
1178
1179        rdmsrl(MSR_PKGC7_IRTL, msr);
1180        if (msr) {
1181                unsigned int usec = irtl_2_usec(msr);
1182
1183                bxt_cstates[3].exit_latency = usec;
1184                bxt_cstates[3].target_residency = usec;
1185        }
1186
1187        rdmsrl(MSR_PKGC8_IRTL, msr);
1188        if (msr) {
1189                unsigned int usec = irtl_2_usec(msr);
1190
1191                bxt_cstates[4].exit_latency = usec;
1192                bxt_cstates[4].target_residency = usec;
1193        }
1194
1195        rdmsrl(MSR_PKGC9_IRTL, msr);
1196        if (msr) {
1197                unsigned int usec = irtl_2_usec(msr);
1198
1199                bxt_cstates[5].exit_latency = usec;
1200                bxt_cstates[5].target_residency = usec;
1201        }
1202
1203        rdmsrl(MSR_PKGC10_IRTL, msr);
1204        if (msr) {
1205                unsigned int usec = irtl_2_usec(msr);
1206
1207                bxt_cstates[6].exit_latency = usec;
1208                bxt_cstates[6].target_residency = usec;
1209        }
1210
1211}
1212/*
1213 * sklh_idle_state_table_update(void)
1214 *
1215 * On SKL-H (model 0x5e) disable C8 and C9 if:
1216 * C10 is enabled and SGX disabled
1217 */
1218static void sklh_idle_state_table_update(void)
1219{
1220        unsigned long long msr;
1221        unsigned int eax, ebx, ecx, edx;
1222
1223
1224        /* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */
1225        if (max_cstate <= 7)
1226                return;
1227
1228        /* if PC10 not present in CPUID.MWAIT.EDX */
1229        if ((mwait_substates & (0xF << 28)) == 0)
1230                return;
1231
1232        rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr);
1233
1234        /* PC10 is not enabled in PKG C-state limit */
1235        if ((msr & 0xF) != 8)
1236                return;
1237
1238        ecx = 0;
1239        cpuid(7, &eax, &ebx, &ecx, &edx);
1240
1241        /* if SGX is present */
1242        if (ebx & (1 << 2)) {
1243
1244                rdmsrl(MSR_IA32_FEATURE_CONTROL, msr);
1245
1246                /* if SGX is enabled */
1247                if (msr & (1 << 18))
1248                        return;
1249        }
1250
1251        skl_cstates[5].disabled = 1;    /* C8-SKL */
1252        skl_cstates[6].disabled = 1;    /* C9-SKL */
1253}
1254/*
1255 * intel_idle_state_table_update()
1256 *
1257 * Update the default state_table for this CPU-id
1258 */
1259
1260static void intel_idle_state_table_update(void)
1261{
1262        switch (boot_cpu_data.x86_model) {
1263
1264        case 0x3e: /* IVT */
1265                ivt_idle_state_table_update();
1266                break;
1267        case 0x5c: /* BXT */
1268                bxt_idle_state_table_update();
1269                break;
1270        case 0x5e: /* SKL-H */
1271                sklh_idle_state_table_update();
1272                break;
1273        }
1274}
1275
1276/*
1277 * intel_idle_cpuidle_driver_init()
1278 * allocate, initialize cpuidle_states
1279 */
1280static void __init intel_idle_cpuidle_driver_init(void)
1281{
1282        int cstate;
1283        struct cpuidle_driver *drv = &intel_idle_driver;
1284
1285        intel_idle_state_table_update();
1286
1287        drv->state_count = 1;
1288
1289        for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
1290                int num_substates, mwait_hint, mwait_cstate;
1291
1292                if ((cpuidle_state_table[cstate].enter == NULL) &&
1293                    (cpuidle_state_table[cstate].enter_freeze == NULL))
1294                        break;
1295
1296                if (cstate + 1 > max_cstate) {
1297                        printk(PREFIX "max_cstate %d reached\n",
1298                                max_cstate);
1299                        break;
1300                }
1301
1302                mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
1303                mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint);
1304
1305                /* number of sub-states for this state in CPUID.MWAIT */
1306                num_substates = (mwait_substates >> ((mwait_cstate + 1) * 4))
1307                                        & MWAIT_SUBSTATE_MASK;
1308
1309                /* if NO sub-states for this state in CPUID, skip it */
1310                if (num_substates == 0)
1311                        continue;
1312
1313                /* if state marked as disabled, skip it */
1314                if (cpuidle_state_table[cstate].disabled != 0) {
1315                        pr_debug(PREFIX "state %s is disabled",
1316                                cpuidle_state_table[cstate].name);
1317                        continue;
1318                }
1319
1320
1321                if (((mwait_cstate + 1) > 2) &&
1322                        !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
1323                        mark_tsc_unstable("TSC halts in idle"
1324                                        " states deeper than C2");
1325
1326                drv->states[drv->state_count] = /* structure copy */
1327                        cpuidle_state_table[cstate];
1328
1329                drv->state_count += 1;
1330        }
1331
1332        if (icpu->byt_auto_demotion_disable_flag) {
1333                wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
1334                wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
1335        }
1336}
1337
1338
1339/*
1340 * intel_idle_cpu_init()
1341 * allocate, initialize, register cpuidle_devices
1342 * @cpu: cpu/core to initialize
1343 */
1344static int intel_idle_cpu_init(int cpu)
1345{
1346        struct cpuidle_device *dev;
1347
1348        dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1349
1350        dev->cpu = cpu;
1351
1352        if (cpuidle_register_device(dev)) {
1353                pr_debug(PREFIX "cpuidle_register_device %d failed!\n", cpu);
1354                return -EIO;
1355        }
1356
1357        if (icpu->auto_demotion_disable_flags)
1358                smp_call_function_single(cpu, auto_demotion_disable, NULL, 1);
1359
1360        if (icpu->disable_promotion_to_c1e)
1361                smp_call_function_single(cpu, c1e_promotion_disable, NULL, 1);
1362
1363        return 0;
1364}
1365
1366static int __init intel_idle_init(void)
1367{
1368        int retval, i;
1369
1370        /* Do not load intel_idle at all for now if idle= is passed */
1371        if (boot_option_idle_override != IDLE_NO_OVERRIDE)
1372                return -ENODEV;
1373
1374        retval = intel_idle_probe();
1375        if (retval)
1376                return retval;
1377
1378        intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
1379        if (intel_idle_cpuidle_devices == NULL)
1380                return -ENOMEM;
1381
1382        intel_idle_cpuidle_driver_init();
1383        retval = cpuidle_register_driver(&intel_idle_driver);
1384        if (retval) {
1385                struct cpuidle_driver *drv = cpuidle_get_driver();
1386                printk(KERN_DEBUG PREFIX "intel_idle yielding to %s",
1387                        drv ? drv->name : "none");
1388                free_percpu(intel_idle_cpuidle_devices);
1389                return retval;
1390        }
1391
1392        cpu_notifier_register_begin();
1393
1394        for_each_online_cpu(i) {
1395                retval = intel_idle_cpu_init(i);
1396                if (retval) {
1397                        intel_idle_cpuidle_devices_uninit();
1398                        cpu_notifier_register_done();
1399                        cpuidle_unregister_driver(&intel_idle_driver);
1400                        free_percpu(intel_idle_cpuidle_devices);
1401                        return retval;
1402                }
1403        }
1404        __register_cpu_notifier(&cpu_hotplug_notifier);
1405
1406        if (boot_cpu_has(X86_FEATURE_ARAT))     /* Always Reliable APIC Timer */
1407                lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE;
1408        else
1409                on_each_cpu(__setup_broadcast_timer, (void *)true, 1);
1410
1411        cpu_notifier_register_done();
1412
1413        pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n",
1414                lapic_timer_reliable_states);
1415
1416        return 0;
1417}
1418
1419static void __exit intel_idle_exit(void)
1420{
1421        struct cpuidle_device *dev;
1422        int i;
1423
1424        cpu_notifier_register_begin();
1425
1426        if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
1427                on_each_cpu(__setup_broadcast_timer, (void *)false, 1);
1428        __unregister_cpu_notifier(&cpu_hotplug_notifier);
1429
1430        for_each_possible_cpu(i) {
1431                dev = per_cpu_ptr(intel_idle_cpuidle_devices, i);
1432                cpuidle_unregister_device(dev);
1433        }
1434
1435        cpu_notifier_register_done();
1436
1437        cpuidle_unregister_driver(&intel_idle_driver);
1438        free_percpu(intel_idle_cpuidle_devices);
1439}
1440
1441module_init(intel_idle_init);
1442module_exit(intel_idle_exit);
1443
1444module_param(max_cstate, int, 0444);
1445
1446MODULE_AUTHOR("Len Brown <len.brown@intel.com>");
1447MODULE_DESCRIPTION("Cpuidle driver for Intel Hardware v" INTEL_IDLE_VERSION);
1448MODULE_LICENSE("GPL");
1449